title: The C825T polymorphism of the G-protein β3 subunit gene and its association with hypertension and stroke: an updated meta-analysis.
abstract: OBJECTIVE
  Several epidemiological studies have evaluated the association between the GNB3 C825T polymorphism and hypertension or stroke. The results of these studies were inconsistent; therefore, we performed a meta-analysis to clarify these discrepancies.
  
  
  METHODS
  We systematically searched the PubMed, Embase, Web of Science, CNKI, and CBM databases, and manually searched reference lists of relevant papers, meeting abstracts, and relevant journals. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for dominant, recessive, and allelic models. A fixed or random effects model was separately adopted depending on study heterogeneity. Subgroup and sensitivity analyses were performed to detect study heterogeneity and examine result stability, respectively. Publication bias was tested using funnel plots, the Egger's regression test, and Begg's test.
  
  
  RESULTS
  We screened 66 studies regarding hypertension and eight concerning stroke. A combined analysis showed that only the allelic model found a marginal association with hypertension (OR = 1.07, 95% CI = 1.01-1.13) and female gender (OR = 1.11, 95% CI = 0.99-1.24). However, no comparison models found an association with stroke (allelic model: OR = 1.11, 95% CI = 0.94-1.32; dominant model: OR = 1.16, 95% CI = 0.92-1.48; and recessive model: OR = 1.05, 95% CI = 0.97-1.14). Sensitivity analysis suggested that all models did not yield a relationship to hypertension or stroke among Asians. Besides, there was a lack of statistical association with hypertension in Caucasians, which maybe due to a small sample size. When we restricted the included studies to normal populations according to the Hardy-Weinberg equilibrium, no association was found.
  
  
  CONCLUSIONS
  There was no evidence indicating that the 825T allele or TT genotype was associated with hypertension or stroke in Asians or hypertension in Caucasians. However, further studies regarding Africans and other ethnicities are needed to identify further correlations.
authors.affiliation: Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Yuzhong District, Chongqing, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Guo
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Zheng
authors.forename: Yun
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiao-Jie
authors.initials: XJ
authors.lastname: Cao
authors.forename: Yan
authors.initials: Y
authors.lastname: Pi
authors.forename: Bing-Hu
authors.initials: BH
authors.lastname: Li
authors.forename: Jing-Cheng
authors.initials: JC
authors.lastname: Li
mesh_terms: D016022:Case-Control Studies; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics*; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D020521:Stroke / Q000235:genetics*
chemical_list: C454420:G-protein beta3 subunit; D020962:Heterotrimeric GTP-Binding Proteins